Systems for slidably mounting exterior vehicle accessories in the beds of pickup trucks or other vehicles having open beds are known. For example, in U.S. Pat. No. 6,116,673, the present Inventor disclosed a slide rail system that is mounted on the upper surface, and partially on an inner surface, of the sidewalls of a vehicle bed by which accessories, such as tool storage boxes or the like, are slidably mounted. The system includes a pair of L-shaped rail support members including a horizontal flange that is placed upon one of the sidewalls and the vertical flanges are placed in parallel alignment inside the bed. The rails are suspended from the parallel vertically disposed flanges and the accessory is slidably contained between the rails upon rollers.
There is room, however, as well as a need for improving prior art slide rails systems. One troublesome area associated with known slide rail systems lies in the top-mounted nature of the design. The required mounting structure necessarily obscures the stake pockets that are typically provided as a standard feature in the sidewalls of vehicle bed. When these stake pockets are obscured by the slide rail system, other accessories cannot be mounted in those stake pockets, which limits the accessory options that are available. In addition, it is not possible to install other commonly desired top-mounted accessories, such as caps, tonneau covers and ladder racks, for instance, when the slide rail system of the '673 patent is installed as described without otherwise first removing the slide rail system.
There is also room to improve the way in which the rails of the slide system are mounted and configured so as to compensate for the degree of taper (or the angle at which the sidewalls deviate from being parallel with the longitudinal axis of the vehicle bed) in order to facilitate the sliding translocation of accessories within the vehicle bed. While the systems of the '673 patent address this problem, these slide rails are typically custom built according to particularly known degrees of taper to provide a specifically tailored parallel rail system therefor. In practice, different rail system models having different taper compensation configurations need to be provided on vehicles made by different manufacturers whose bed sidewalls have different signature taper specifications. While the prior art rail systems may be individually useful in association with a particular vehicle bed having a corresponding degree of taper, a great deal of time and precision are still required to measure and obtain the appropriately corresponding and compensating angles required to actually mount and secure the rails in proper parallel alignment.